In this article, we’ll provide some tips on what to put under rocks to prevent weeds from infiltrating your garden.
Landscaping rocks offer a beautiful and practical ground cover option for gardens, significantly reducing water usage and the need for frequent mowing.
Unlike lightweight mulch, rocks do not blow away and remain durable over time. However, when weeds start sprouting, they can spoil the beauty of your garden.
What To Put Under Rocks To Prevent Weeds
1. Landscape Fabric: A Breathable Option
Landscape fabric serves as a useful weed barrier, offering the advantage of allowing water, nutrients, and air to reach the soil and plants.
Compared to plastic, it is lighter and more breathable, creating a healthier environment for your garden.
Overlapping the fabric pieces ensures no gaps for weed growth. Use rocks or landscape staples along the edges to keep the fabric in place effectively.
A thin layer of mulch, such as bark chips or stone, can conceal the landscape fabric. However, avoid laying excessive mulch, as it can lead to enriched soil on top of the fabric, potentially fostering weed growth.
You may also be interested in learning about how to keep weeds out of mulch.
Types Of Landscape Fabric
- Perforated: Featuring pre-cut holes for water and air passage, this lightweight fabric is easy to tear.
- Spun: This durable fabric with circular or swirling patterns resists punctures and tears, lasting for many years. You may need to cut holes to accommodate plant growth and tree roots.
- Woven: With its criss-cross pattern, woven landscape fabric enables water and air to access the soil beneath. You can cut holes for larger roots to penetrate without risking punctures.
Benefits Of Landscape Fabric
- Easy Handling: Coming in rolls, landscape fabric is easy to manage during installation.
- Soil Stabilization: Landscape fabric prevents rocks and supporting gravel or sand from sinking into the soil, providing stability and reducing erosion.
While landscape fabric offers effective weed prevention for a few years, organic material buildup and wind-carried weed seeds may lead to regrowth.
2. Plastic For Garden Cover
Using a black plastic sheet as a weed barrier beneath landscaping rocks can be an effective way to reduce unwanted vegetation.
Its large size allows for seamless coverage, eliminating the need for overlapping pieces that could create spaces for weeds to grow through.
Disadvantages Of Plastic:
- Aesthetic Impact: The plastic corners may protrude through the rocks, compromising the landscape’s appearance.
- Environmental Concerns: Plastic is not environmentally friendly, posing a drawback for eco-conscious gardeners.
- Impermeability: The lack of permeability in plastic prevents rainwater from reaching the soil, depriving nearby plants and lawns of necessary moisture. The absence of oxygen can also suffocate soil organisms, leading to potential root rot. To address these issues, consider leaving holes in the plastic around bushes to allow water and air to flow through.
- Prone to Damage: Plastic is susceptible to tearing, which could diminish its effectiveness as a weed barrier.
3. Newspaper And Cardboard As Weed Barriers
Newspaper and cardboard serve as effective short-term solutions for preventing weed growth in your garden.
When opting for these materials, layer them with multiple sheets to slow down their decomposition rate. Overlapping each layer minimizes the chances of weeds finding their way through any gaps.
Considerations For Effective Usage
- Avoid Colored Pages: When using newspaper, steer clear of colored pages to prevent chemical seepage into the soil, which could be harmful to your plants.
- Balancing Decomposition: To avoid excessive carbon accumulation in the soil, refrain from using too much newspaper, especially if you plan to grow plants in the area. If necessary, consider using a high-nitrogen fertilizer to maintain a balanced soil composition.
Limitations Of Cardboard And Newspaper
While these options are cost-effective, they do have their drawbacks.
Both cardboard and newspaper degrade relatively quickly, eventually losing their weed-stopping effectiveness. As they decompose entirely, your landscaping rocks may begin to sink into the soil, compromising the aesthetics of your garden.
It’s essential to acknowledge that newspaper or cardboard needs regular replacement, which can be time-consuming. However, the advantage lies in the recyclability of these materials, allowing you to contribute to sustainable gardening practices.
Despite using cardboard or newspaper, it’s crucial to understand that no solution can entirely eliminate weed growth. Regular maintenance and weeding of your rock garden are necessary to preserve its pristine appearance.
How Do You Prevent Weeds From Growing Through Rocks?
Before laying down the landscaping rocks, it’s essential to carefully select a weed-free area.
If weeds are present, here are some options:
1. Using Non-Selective Herbicides
You can use a non-selective herbicide to target and eliminate weeds (find how to kill thistle weeds).
However, be cautious not to spray it on your desirable plants or bushes, as it may harm them. Use a large piece of cardboard or plastic as a shield to protect surrounding plants.
Find out our top pick for the best weed killer for lawns.
2. Removing Weeds Manually
Alternatively, dig out the weeds and their roots from the area (use the best weeding tool). Be thorough to prevent regrowth. If you need to do this quickly, wear protective gloves and a face mask.
3. Caution With Salt Usage
Avoid using salt as a weed killer, as it can negatively affect your existing bushes by altering the soil’s salinity levels. Additionally, it may hinder the growth of new shrubs.
4. Boiling Water Method (For Small Areas)
Pouring boiling water on weeds can be a simple and natural way to kill them. However, it is practical only for small areas due to the labor-intensive process. Be cautious and wear suitable clothing to avoid burns.
5. Utilize Horticultural Vinegar For Stubborn Weeds
While household white vinegar might have some weed-killing properties, it may not be powerful enough for all types of weeds.
Instead, consider purchasing horticultural vinegar, available online or at home improvement stores, for more effective results.
Prep Work For Long-Term Weed Prevention
For long-term prevention, consider these preparatory steps:
Plastic Cover Method
If you can afford to wait, cover the area with plastic during sunny and warm weather for around 6 weeks or more. This process will effectively kill the weeds beneath the plastic.
Note that this method is ineffective during cold weather.
Ample Compost Enrichment
Prior to laying the landscaping rocks, ensure the soil is enriched with plenty of compost. Once the rocks are in place, it becomes challenging to amend the soil, so proper preparation beforehand is crucial.
Steel Edging Border
Install a steel edging border around 3 to 4 inches high. This barrier will prevent weeds, grasses, and plants from taking root in the rock beds (also check out how to kill grass and weeds).
FAQs – How To Prevent Weeds Under Rocks
1. What is best to put under rocks to prevent weeds?
The best option to put under rocks to prevent weeds is landscape fabric or weed barrier fabric.
2. Should I use landscape fabric or plastic under rocks?
Landscape fabric is preferable over plastic as it allows water and air penetration while blocking weeds.
3. What is the best thing to put under gravel to prevent weeds?
A geotextile fabric or landscape fabric is the best choice to put under gravel and prevent weed growth.
4. What is an alternative to landscape fabric under gravel?
An alternative to landscape fabric under gravel is using layers of newspaper or cardboard.
5. Should I use landscape fabric under gravel?
Yes, landscape fabric is recommended under gravel to prevent weed penetration while still allowing drainage.
6. What to put under river rock?
Under river rock, you can use landscape fabric or geotextile fabric to inhibit weed growth.
7. How to replace landscape fabric under rocks?
To replace landscape fabric under rocks, remove the rocks, old fabric, and any weeds, and then lay down new landscape fabric before placing the rocks back.
8. What are the pros and cons of landscape fabric under gravel?
The pros of landscape fabric under gravel include weed prevention and soil erosion control, while cons may include reduced water penetration and potential difficulty in removal if not properly maintained.
Final Thoughts: What To Put Under Rocks To Stop Weeds
To prevent weeds under rocks, you can use a layer of weed barrier fabric or landscape fabric before placing the rocks.
Incorporating newspaper or cardboard as weed barriers offer a short-term and budget-friendly approach to managing weed growth in your garden.
By understanding their limitations and knowing when to replace them, you can make the most of these materials to keep your landscape weed-free (learn how to get rid of winter weeds).
Remember to combine their usage with regular weeding to ensure your rock garden remains a captivating and well-maintained focal point of your outdoor space.